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The Coated Woodfree Market

These papers are generally the highest quality printing papers available. They are very smooth, usually have a blue-white shade and can produce very high resolution prints. Most commonly theses papers are printed sheet fed offset and heat set offset. Generally stiffness and opacity are valued most highly by NA printers while in Europe printability and smoothness are king. Higher levels of pigments are used in filling the base sheet and from the use of higher coat weights in Europe as compared to NA or even Asia. Double and triple coating are used quite often in order to gain high levels of smoothness, increase the mineral content and reduce the fiber content. Coated woodfree is usually made on an alkaline machine. This allows high levels of carbonate to be used.

Generally Carbital 60 is used as a base coat pigment in NA for good coverage, but because higher coat weights and more layers are applied in Europe finer pigments are often used in the base and middle coat layers such as Carbital 90 and are usually partnered with a kaolin pigment. Fine glossing clays like Astrasheen are commonly used as a partner with fine carbonate pigments in the top coat. Contour Xtreme has introduced a new level of design flexibility. This fine platy pigment is highly efficient and allows higher levels of carbonate while achieving good printability, gloss and smoothness. Heat set offset grades are usually single coated and require good blister resistance in the dryer section after printing. Alphatex and Deltatex improve blister resistance dramatically by making the coating more open. Engineered kaolins like Astra-Plus, Alphaprint 100 and Capim DG also open the coating and make it more blister resistant.